6 In Line Gotoh 510 tuners, sold as a set of 6. 15:1 ratio. Magnum locking - simply insert the string through the hole, pull to tension by hand and begin tuning. As you tune, only the locking cam in the post turns. Once the string begins to turn, it can be tuned to pitch. In less than one revolution of the post, you will be in tune and locked. The Gotoh 510 tuners are probably the best machineheads on the market today. The unique Lubri-Plate coating on the gears creates less friction and provides an ultra smooth feel with minimal back lash and unrivalled tuning stability. Gotoh's Rock-Solid string posts eliminate looseness for perfect tuning stability. 10mm diameter pegholes are required. Screws, washers and threaded hex bushings are included.